Peter is a mathematician and software developer who specialises in the use of numerical and statistical modelling techniques. Following his first degree, he worked at Harwell on problems related to radioactive waste disposal including development of finite element codes and probabilistic safety assessments methods. His doctoral thesis looked at modelling flow and transport in fractured rocks using what are now known as discrete fracture networks. He has developed numerous computer codes for performance assessment of radioactive waste disposal systems for various international clients, while acting as a reviewer for major international programmes. For 25 years he has worked in small scientific consultancy companies, joining Quintessa in 2000 and becoming a director in 2002. He supports and develops Quintessa’s general-purpose software tools, AMBER and QPAC. Over the last few years he has applied statistical modelling techniques to support safety cases for the UK fleet of advanced gas-cooled reactors. Peter is a director of Quintessa Limited.